Cannot Upload Avatars anymore

Hoping someone can please help...

I cant upload files to my media library anymore as well as buddypress avatars, get this error:

Upload Failed! Error was: The uploaded file could not be moved to the upload folder.

I have tried the suggestions from drmike on this thread about WPMU AND BUDDYPRESS - Upload issue with no luck.

My host says that someone ran this... command: chown -R thatmlmb:thatmlmb public_html in ssh

Quite certain no one has access to my account. I was upgrading plugins automatically at that time, not sure if / how that can have something to do with it?

I re uploaded all my wordpress files and upgraded buddypress to 1.2.4.1 but that didnt fix it.

Thanks for the help!